Question: What do the following two equations represent? $4x-y = -4$ $-16x+4y = 5$
Answer: Putting the first equation in $y = mx + b$ form gives: $4x-y = -4$ $-y = -4x-4$ $y = 4x + 4$ Putting the second equation in $y = mx + b$ form gives: $-16x+4y = 5$ $4y = 16x+5$ $y = 4x + \dfrac{5}{4}$ The slopes are equal, and the y-intercepts are different, so the lines are parallel.